A typical data disk drive includes at least one data disk where virtually the entire capacity of the data disk is available for data storage. A small portion of the data disk is set aside as a system area for storing system related information. The data disk is configured by the factory or by an OEM to exclude the system area from general access. As such, the system area remains "locked" or unavailable for storing user data.
Managing or changing the available capacity of such a disk drive after the disk drive has been placed in service in a data processing system requires reconfiguration of the disk drive to "unlock" the system area. Reconfiguration is performed by the OEM, or by an end user, by performing a series of steps commanding the disk drive to, for example, make at least a portion of the system area available for limited access. However, the capacity unlocked is a small fraction of the native capacity of the hard disk, and the user virtually does not gain any additional useable storage capacity from the hard disk
Further, due to the minimal amount of hard disk capacity unlocked, there has not been a need for robust security methods to prevent widespread unauthorized reconfiguration of the disk drive and use of the system area. As such, existing security methods are not suited to deter prohibited access to protected areas on the data disk or to prevent illegal reconfiguration of the hard disk drive.
With the increasing capacity offered by data disk drives and other memory devices, it is highly desirable to securely manage the amount of the available capacity to enable commercial models such as "fee for use". There is, therefore, a need for a system and a method of managing the available capacity of disk drives and memory devices while in service in various data processing systems. There is also a need for such a system and method to provide an efficient and robust security process for preventing unauthorized use of said available capacity.